A method for manufacturing an array substrate in the related art includes forming on a base substrate a pattern of a gate metal layer, a pattern of an active layer, a pattern of a source and drain metal layer, a pattern of a passivation layer and a pattern of a transparent conductive layer in order, and each pattern of the above layers is manufactured through such steps as depositing and coating a photoresist, exposing, developing, etching and removing the photoresist and the like.
In a manufacturing process, foreign matters such as dust and chippings are inescapably attached onto the film layers due to the environment, device and other abnormal factors. Theses foreign matters may be attached during the depositing process, the photoresist coating process or the dry etching process. When etching the active layer by the dry etching process, an etching gas may not contact the active layer and react with the same due to the foreign matters attached thereon, and then the portions of the active layer attached with the foreign matters may be remained. As a result, light spots may occur, and the yield of the array substrate may be affected adversely.